Interlocking control apparatus



Patented Oct. 30, 1945 INTERLO CKING C ONTROL APPARATUS Ronald A. McCann, Swiss vale, Pa., assignor to The Union Switch & Signal Company, SWISS- vale, Pa., a corporation of Pennsylvania Application June 8, 1944, Serial No. 539,234 I 6 Claims.

My invention relates to interlocking control apparatus, and particularly to interlocking control apparatus in which manual control devices such for example as push buttons, which are free to be operated at any time, are provided for controlling the signals and track switches of a railway interlocking layout.

In interlocking plants having overlap control of signals, such for example as in interlocking plants employing train stops, it is necessary to extend the locking distance of certain switches or crossovers in order to prevent the operation of such switches or crossovers from causing an approach signal to be returned to the stop indication after it has been cleared.

One feature of my invention is the provision of means for storing the control for a route when a switch or crossover in the route is locked because the extended locking section is occupied by a car or train while the section in which the switch or crossover is located is unoccupied.

I shall describe one form of apparatus embodying my invention, and shall then point out the novel features thereof in claims,

In the accompanying drawings, Figs. 1a to 1e, inclusive, are diagrammatic views showing one form of apparatus embodying my invention, in which Fig. 1a shows a layout of switches and si nals in an interlocking plant, together with switch and signal operating circuits, signal control circuits, and control means for a switch indication relay; Fig. 1b shows route selector circuits for the layout of Fig. la controlled by manual control devices shown in Fig. 1d; Fig. 1c shows circuits for controlling switch locking relays and switch control and indication relays, and also an approach locking relay associated. with a given approach signal; Fig. 1d shows a track model or diagram for the interlocking layout of Fig. 1a divided into indication sections, and shows manually controllable push buttons arranged in the track model at points corresponding to the signal locations; and Fig. 1c shows circuits for controlling indication lamps for two of the indication sections of Fig. 111.

Similar reference characters refer to similar parts in each of the views.

In each of the views, contacts operated by the various relays or other devices are identified by numbers, such numbers having distinguishing prefixes from which they are separated by a dash when the contacts are shown apart from the relay by which they are operated. The prefix' for circuits which are not traced in this specification, I

are identified by the reference character for the relay by which they are operated, followed by a dash, without a number after the dash, For example, contact lANS-, shown in the stick circuit for relay 2X8 in Fig. 1b, is identified by the reference character IANS for relay IANS by which this contact is operated, followed by only a dash.

Referring first to Fig. 1a, a, track layout is shown, in which two parallel tracks are interconnected by a crossover including track switches designated by the reference characters Al and Bi In order to simplify the drawings, each track, comprising two parallel series of track rails, is represented by a single line.

These tracks are divided by insulated joints 7 to form switch sections designated by the reference characters AIT and BIT in which switches Al and BI, respectively, are located, extended locking sections designated by the reference characters ET and ST, and approach sections designated by the reference characters MIT and AIUT erence character for the respective relay by which associated with an approach signal l0. Each of these track sections is provided with a track circuit including a suitable source of current such as a battery 9, connected across the rails adjacent one end of the section, and a track relay, designated by a reference character which is the same as the reference character for its section except that it includes the letter R instead of the letter T, connected across the rails adjacent the opposite end of the section.

Traffic movements toward the left, as shown in the drawings, 'which I shall assume is the southbound direction, over switches Al and BI, are governed by home signals designated by the reference characters 6 and 8, respectively. An approach signal I0 is provided for signal 6. Traffic movements in the opposite or northbound direction, over switches Al and BI, are governed by signals 2 and 4, respectively. The signals may be of any suitable design, such for example as the semaphore or the searchlight type.

Switches Al and BI are operable to their normal positions; in which they are shown in the drawings, or to the opposite or reverse positions, by mechanisms designated by the reference characters AIM and BIM, respectively. Mechanisms AIM and BIM are in turn controlled by a polarized switch control relay IW, shown in Fig. 10.

A polarized switch indication relay IP is controlled similarly to relay 'IWP described in Letters Patent of the United States No. 2,301,297

eluding a front contact of asignal relay I 011,

This relay is controlled by a manually operable lever IOV having a normal position n and a reverse position r, by extended locking section track relay 6R when switches AI and BI are in the normal position, by extended locking section track relay 8R and switch section track relay BIR when switches. AI and BI are in the reverse position, and also by switch. section track relay AIR and by approachsection track relay IIIR;

Referring now to Fig. 1b, circuits. are here shown for controlling route, selector relays and exit stick relays by manual route control push buttons which are shown in Fig. 1d designated by the reference character P preceded by the reference character for the signal for the corresponding route end. Each of the push buttons operates a circuit controller which is of the pushpull. type, such for example as shown in Letters Patent of the United States No 2,295,301 granted September 8, 1942 to W. E. Smith for Circuit controllers. to a mid stroke position, and has a normally open contact and a normally closed contact such for.

example as contacts 42 and 96, respectively, of controller 4P shown at the left-hand end of Fig. 11). Contact 42 becomes closed when button AP is pushed in, and contact 95 becomes opened when button 4P is pulledout.

Each exit stick relay is desi nated by the reference character XS preceded by a number corresponding to that of the push button by which it is controlled. The other relaysshown in Fig.v

1b are route selector relays designated by the reference character N or S for northbound or southbound, respectively, preceded by reference character N or R for the normal or the reverse position, reactor N or R for the normal or the reverse position, respectively, of a track switch, which is in turn preceded by a reference character number for the switch.

The circuits for energizing each of the route selector relays IANS, IRS and IBNS are arranged for storing the control for the corresponding route if a leverman pushes the buttons .for setting up the corresponding route while the switches are locked because the extended locking section for that route is occupied, although the switch sections AIT and BIT are unoccupied.

In Fig. lo, a first switch locking relay, designated by the reference character I LR, is shown controlled by approach or time looking relays designated by the reference characters ZAS, 4AS, GAS and 8AS, and by switch section track relays AIR and BIR. Relays ZAS, 4AS, GAS and BAS may be controlled similarly to relay ZAS shown in Fig. 1F of the Lewis patent referred to.

A second switch locking relay, designated by the reference character ILS,,is controlled by the first switch locking relay ILR, and by extended locking section track relay 6R if the switchesare reversed and signal I I] is controlled to. display a Each of these controllers is. biased proceed indication, or by extended locking section track relay 8R if the switches are normal and signal I0 is controlled to display a proceed indication, as well as by a switch lever IV having a middle position 0. Lever IV has also reverse positions n and r for efiecting operation of switches AI and BI to normal and reverse positions, respectively.

A polarized lever repeater relay IVP is controlled by relay ILS and by lever IV, and also by the route selector and exit stick relays.

Circuits are shown including contacts of relays ILS and .IVP for controlling polarized switch control relay I W.

Normal and reverse switch repeater relays INC and IRC, respectively, are shown controlled by polarized switch control relay I W and by polarized switch indication relay IP,

Normal and reverse switch indication relays INWK and IRWK, respectively, are controlled byrelays INC and IRC, and by relay IW.

Circuits are also shown in Fig. 1c for controlling approach locking stick relay IOAS associ-' ated with signal III.

In Fig. 1d, a track model or diagram is shown divided into indication sections including sections IRK and IBNK. Push buttons 2P, 4P, SP and BP are arranged in the track model at points corresponding to the locations of signals 2, 4, i and 8, respectively, in the layout of Fig. 1a.

In Fig. 1e, circuits are shown controlled by a coding device CD for controlling indication lamps IBNE and IRE for sections IBNK and IRK, respectively, to display a flashing indication if the indication selector relay AI SP is deenergized and the switches of a corresponding route are locked in a given position because of a train on one of the extended locking sections, so that relay ILS is deenergized while relay ILR is energized.

Having described, in general, the arrangement and control of the apparatus shown by the accompanying drawings, I shall now describe, in detail, its operation.

As shown by the drawings, all parts are in their normal condition, that is, switches AI and BI are in their normal positions; all signals are indicating stop; all track sections are unoccupied, and hence the track relays are energized; lever IV is in its center position 0; lever IUV is in its normal position 11; the controllers operable by buttons 2P, 4P,.6P and 8P are in: their biased mid stroke positions; relays 2AS, 4AS, GAS, 8AS, IIJAS, ILR, ILS and INC are energized; relay .IP is energized by current of normal polarity; coding device CD is intermittently energized; and relays IIIH, IVP, IW, IRC, INWK, IRWK, AISP, and the route selector and exit stick relays. shown in Fig. 1b are deenergized.

The'circuit by which relay ILR is energized passes from terminal B of-a suitable source of current, through contacts II, I2, I3'and I I of relays ZAS, 4AS, GAS and, BAS, respectively, contacts AIR-I5 and BIR-IB, and. the winding of relay ILR to the other terminal 0. of the same source of current.

A pick-up circuit is closed for relay ILS, passing from terminal B, throughcontact ILRI'I, contact 6RI 8 in multiple with contact INC-I9, contact 8R20, winding of relay ILS, and contact 22 of lever IV in-its 0 position, to terminal 0. A pick-up circuit is also, closed for relay I LS, passing from terminal B, through contacts ILR-I1 and I.0AS.2I, winding of relay ILS, and contact 22' of lever IV' to terminal 0. Stick circuits are also closed for relay ILS, which are the same as the pick-up circuits just traced except including contact 230i relay ILS instead of contact 22 of lever IV.

Both a pick-up and a stick circuit are closed for energizing relay IUAS, the pick-up circuit passing from terminal B, through contacts IIIH- 24, IDR25 and AIBR-Zfi, and the winding of relay [OAS to terminal 0. The stick circuit passes from terminal B, through contact IOH-24, front point of contact 28 of relay IUAS, and the winding of relay WAS to terminal 0. 1

Relay INC is energized by a circuit passing from terminal B, through contact IP--29, contact IP- 30 closed in the left-hand position, winding of relay INC, and contact 3I of relay IW closed in the left-hand position, to terminal 0.

Coding device CD is intermittently energized by a circuit including its own back contact 32.

I shall assume that a leverman decides to set up a route for a southbound train to proceed past signal 8 over switch BI in the normal position. He will therefore push the button 8?, causing relay IBNS to become energized by a circuit passing from terminal B, through contact BIR-33, contact 34 of the controller operated by button 8?, back point of contact IBNN35, winding of relay IBNS, contact XS-38 in multiple with contact IRN39, contact IRS-40, and the back point of contact IRWK4I to terminal 0. Relay IBNS, upon becoming energized, completes a stick circuit for relay IBNS, which is the same as the pick-up circuit just traced for this relay except that it includes a circuit path through contact 36 of the controller operated by button 8?, and contact 31 of relay IBNS, instead of the circuit path through contact 34 of the controller operated by button 8P, and the back point of contact IBNN-35.

The leverman will then push button 4P. Relay 4X8 will therefore become energized by its pickup circuit passing from terminal B, through contact 42 of the controller operated by button 4P, front point of contact IBNS43, contacts IRN- 44 and IBNN-45, and the winding of relay 4X8 to terminal 0. Relay AXS, upon becoming energized, completes its own stick circuit passing from terminal B, through contact IBNS-4$, contact 48 of relay 4X8, and the winding of relay 4X8 to terminal 0.

With relays IBNS and IXS energized, a circuit is completed for energizing relay IVP by current of normal polarity, this circuit passing from terminal B, through contact 49 of relay ILS, left portion of the winding of relay IVP, and contacts IBNS50 and iXS5I to terminal 0. The closing of this circuit causes no change in the position of contacts 52 and 55 of relay IVP which are already in the normal position.

Relay IW, however, is now energized by a normal control circuit passing from terminal B, through contact 52 of relay IVP in the left-hand position, front point of contact 53 of relay ILS, winding of relay IW, front point of contact 54 of relay ILS, contact 55 of relay IVP in the left-hand position, and contacts IBNS50 and IXS5I to terminal 0.

Relays IP and INC are already enerized as previously described.

With relay IW energized, relay INWK now becomes energized by a circuit passing from terminal B, through contact IW56, front point of contact 51 of relay INC, and the winding of relay IN'WK to terminal 0.

Signal 8 will now be cleared by circuits which are similar to the circuits shown for controlling the signals in the Lewis patent referred to. Relay 8AS will therefore become deenergized, causing relay ILR to also become deenergized. Relay ILR, upon becoming deenergized, causes relay ILS to become deenergized.

The normal control circuit for relay IW, through contacts 53 and 54 of relay ILS, will now be opened, and a normal retaining circuit for this relay will be closed, passing from termi nal B, through contact IW--58 closed in thelefthand position, contact IP-59 closed in the lefthand position,.back point of contact 53 of relay ILS, winding of relay IW, back point of contact 54 of relay ILS, and contact IP-60 closed in the left-hand position to terminal 0.

I shall now assume that a southbound train passes signal 8 and enters section BIT. Relay BI R will therefore become deenergized, and henc contact BIB-33 will be opened in the stick circuit previously described for relay IBNS, causing relay IBNS to become deenergized. With relay IBNS deenergized, the stick circuit previously traced for relay IXS will be opened at contact IBNS- IG, and hence relay 4X5 will also become deenergized. The circuit for relay ILR will now be opened at contact BIR--I6, so that although relay 8AS becomes energized as the train enters section BIT, relay ILR will remain deenergized, and therefore relay ILS will also remain deenergized.

When the train enters section 8T, contact 8R20 in some of the pick-up .and stick circuits traced for relay ILS will also be opened.

When the train leaves section BIT, relay BAS having already become energized on account of the arm of signal 8 being returned to the stop position, relay ILR will again become energized by its circuit previously traced. Relay ILS will now become energized by its pick-up circuit including contact IIJAS--2I if signal I0 has not been cleared.

I shall further assume,that, while the train has been proceeding over the route controlled by signal 8, signal I0 has been cleared by the leverman moving lever IllV to its r position. Relay IOH. is therefore energized by its circuit passing from terminal B, through contact BI of lever IUV closed in the 1 position, contacts BR-BZ and INC-6B, contact 61 of relay AIR, contact 68 of relay IIIR, and the winding of relay IOI-I to terminal 0. With relay IIIH energized, the arm of signal In is operated to the proceed position by a circuit including contact 69 of relay IOI-I. Relay IOH, upon becoming energized, opens its contact NIH-24 in the circuits for relay IIIAS, causing relay IUAS to become deenergized. With relay IBAS deenergized, contact MAS-2| will be opened in the circuits for relay ILS, causing relay ILS to remain deenergized or to become deenergized, while the train is occupying section 8T, according as the train is still occupying section BIT or has left this section.

I shall next assume that, after the train leaves section BIT and while it is still occupying section 8T while sections AIT and BT are unoccupied, the leverman decides to arrange for a route, controlled by signal 6, over switches AI and BI reversed. As already described, relay ILR has become energized by its circuit previously traced when the train left section BIT. Switches AI and BI are now locked in their normal positions because relay ILS' is deenergized.

However, with relays INWK and ILR energized, the leverman can energize relay IRS by depressing. button 6P; The circuit by 'whi'ch're lay IRS becomes energized passes. from terminal B, through contact AIR-l0, contact ll of the controller operated by button 6P, back point. of contact IRN1 2, winding of relay IRS, contact 2X80, contact 8| of relay 8X8, contacts IA-NN-82 and IBNS-BS, front point of contact INWK-84, and contact ILR85 to terminal '0. Relay IRS, upon becoming energized, completes a stick circuit for relay IRS which is the same as the pick-up circuit just traced except that it includes contact I4 of the controller operated by button GP and contact 19 of relay IRS instead of contact 11 of thecontroller operated by button SP and the back point of contact IRN'|2.

The leverman will then depress push button 4P, thereby completing a second pick-up circuit for relay fiXS whichgisthe same as the pick-up circuit; previously traced: 'for this relay except, that. it includes the back point of contact I BN S 43 and the front point of contact IRS86 instead of the front point of contact IBNS--43. A stick circuit for relay 4XS will then be completed whichis thc same as the stick circuit-previously traced for this relay. except that it includes contact I.RS-4I instead of contact IBNS-Mi.

To inform the leverman that switches AI and BI are locked in the normal position because of the train on the extended locking section 8T, and that they can therefore not, at this time, be operated to the reverse position in response to his operation of buttons GP and AP for arranging the route governed by signal 6, indication lamp IBNE will become lighted, and display a flashing indication, by a circuit passing from terminal B, through contact 81 of coding device CD, contacts ILS88, ILR-89, INWK90, and IBNN-SI, the back point of contact 92 of relay AISP, and lamp IBNE to terminal 0.

The reverse control for switches AI and BI will be stored by relays IRS and 4X5, and relay IlJI-I will remain energized because contact INC66 will remain closed, and hence signal III will continue to display the proceed indication.

As soon as the train leaves section 8T, relay ILS will become energized b its pick-up circuit including contact 8R-20, previously traced. With relay ILS energized, its contact ILS-88 will open, and will thereby extinguish lamp IBNE. With. relay ILS' energized, a circuit will now be completed for energizing relay I VP by current of reverse polarity, this circuit passing from terminal B, through contact 49 of relay ILS, righthand portion of the winding of relay IVP, and contacts IRS-93 and 4XS-9 l to terminal 0.

Contacts 52 and 55 of relay IVP will therefore become closed in the right-hand position, there-- by completing a circuit for energizing relay I W by'current of. reverse polarity, this circuit passing from terminal B, through contact 55 of relay I VP closed in the right-hand position, front point of contact 54 of relay ILS, winding of rela IW,

front point of contact 53 of relay ILS, contact 52 of relay IVP closed in the right-hand position, and contacts IRS-93 and 4XS94 to terminal 0. With relay IW energized by current of reverse polarity, switches AI and BI will be operated to the reverse positions by the mechanisms AIM and BlM which will be energized by circuits passing from terminal B, through contact |W9l, and through contact IW-98 closed in the right-hand position, as indicated in Fig. 10L.v

Upon completion of the operation of switches Al and BI to the reverse positions, relay IP will become energized by current of reverse polarity,

Relay INC will become de'energized when relay 'IW' becomes energized by current of reverse p0- larity, and relay IRC will become energized, when relay IP also becomes energized by current of reverse polarity, by a circuit passing from terminal B, through contact I.P-29, contact IP-30 closed in the right-hand position, winding of relay IRC, and contact 3| of relay IW closed in the right-hand position to terminal 0.

Relay INWK will now be deenergized, and relay IRWK will become energized by a circuit passing from terminal B, through contact IW-56, back point of contact 51 of relay INC, contact of relay IRC, and the winding of relay IRWK to terminal 0. Relay AISP Will then become energized by a circuit passing from terminal B, through contacts GAS-99 and IRWK- Iflfl, and the winding of rela AISP to terminal 0. With relay AISP energized, a circuit, only a. portion of which is shown, including the front point of contact I-IJI of relay AI SP, will be completed for energizing lamp IRE to display a stead indication.

During the operation of switches AI and BI to the reverse positions, relay IOH will. remain energized on. account of contacts lift-62 and 8R 64,. and contact 65 of relay BIR being closed, and hence signal III will continue to display the proceed indication.

Although I have herein shown and described only one form of apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In interlocking control apparatus for a first route extending from a given home signal along a given railway track over a given switch in the normal position and for a second route extending from said home signal over said switch in the reverse position, including a switch section in which said switch is located and a first and a second extended locking section in said first and said second route respectively beyond said switch section, including an approach signal for said home signal controlled over said first or said second extended locking section if said switch is in the normal or the reverse position respectively, the combination comprising, a first locking relay for said switch, a circuit for energizing said first locking relay if said switch section is unoccupied and said home signal indicates stop, a second locking relay for said switch, means controlled by a front contact of said first locking relay for energizing said second locking relay if said first extended locking section is unoccupied or said switch is in the normal position and if said second extended locking section is unoccupied or said switch is in the reverse position, and manually controllable means effective if said first looking relay is energized for preparing a circuit for effecting operation of said switch as soon as said second locking relay becomes energized.

2. In interlocking control apparatus for a first route extending from a given home signal along a given railway track over a given switch in the normal position and fora second route extending from said home signal over said switch in the reverse position, including a switch section in which said switch islocated and a first and a second extended locking section in; said first and said secondroute respectively beyond said switch section, including an approach signal for said home signal controlled over said first or said second extended locking section if said switch is in the normal or the reverse position respectively, the combination comprising, a locking relay for said switch, means for energizing said locking relay if said switch section is unoccupied and if said first extended locking section is unoccupied or said switch is in the normal position and also if said Second extended locking section is unoccupied or said switch is in the reverse position, and manually controllable means effective if said switch section is unoccupied for preparing a circuit for effecting operation of said switch as soon as said locking relay becomes energized.

3. In interlocking control apparatus for a first route extending from a given home signal along a given railway track over a given switch in the normal position and for a second route extending from said home signal over said switch in the reverse position, including a switch section in which said switch is located and a first and a second extended locking section in said first and said second route respectively beyond said switch section, including an approach signal for said. home signal controlled over said first or said second extended locking section if said switch is in the normal or the reverse position respectively, the combination comprising, manually controllable means for energizing route control apparatus for each of said route if said switch section is unoccupied, and means controlled by the route control apparatus for each of said routes for then setting up the corresponding route when its extended locking section becomes unoccupied.

4. In interlocking control apparatus for a first route extending from a given home signal along a given railway track over a given switch in the normal position and for a second route extending from said home signal over said switch in the reverse position, including a switch section in which said switch is located and a first and a second extended locking section in said first and said second route respectively beyond said switch section, including an approach signal for said home signal controlled over said first or said second extended locking section if said switch is in the normal or the reverse position respectively, the combination comprising, manually controllable means for energizing route control apparatus for each of said routes and for then retaining it in the energized condition if said switch section is unoccupied, and means controlled by the route control apparatus for each of said routes for then setting up the corresponding route when its extended locking section becomes unoccupied.

5. In interlocking control apparatus for a first route extending from a given home signal along a given railway track over a given switch in the normal position and for a second route extending from said home signal over said switch in the reverse position, including a switch section in which said switch is located and a first and a second extended locking section in said first and said second route respectively beyond said switch section, including an approach signal for said home signal controlled over said first or said second extended locking section if said switch is in the normal or the reverse position respectively, the combination comprising, manually controllable means for energizing route control apparatus for each of said routes if said switch section is unoccupied, indication means controlled to display a flashing indication if said switch section is unoccupied and if one of said extended locking sections is occupied, and means controlled by the route control apparatus for each of said routes for setting up the corresponding route when its extended locking section becomes unoccupied.

6. In interlocking control apparatus for a first route extending from a given home signal along a given railway track over a given switch in the normal position and for a second route extending from said home signal over said switch in the reverse position, including a switch section in which said switch is located and a first and a second extended locking section in said first and said second route respectively beyond said switch section, including an approach signal for said home signal controlled over said first or said second extended locking section if said switch is in the normal or the reverse position respectively, the combination comprising, manually controllable means for energizing route control apparatus for each of said routes if said switch section is unoccupied and if said home signal indicates stop, and means controlled by the route control apparatus for each of said routes for then setting up the corresponding route when its extended locking section becomes unoccupied.

RONALD A. MCCANN. 

